Phase I--II evaluation of a new anthracycline antibiotic, aclacinomycin A, in adults with refractory leukemia.

Aclacinomycin A (ACM) is a new anthracycline antibiotic that produces substantially less cardiotoxicity in animals than does doxorubicin. To define the effective dose for the treatment of patients with leukemia, we treated 43 patients with acute nonlymphoblastic leukemia (ANLL) or acute lymphoblastic leukemia (ALL) using ACM administered at three dose levels. All patients had previously received extensive treatment with other chemotherapy; their median cumulative dose of prior anthracycline was 340 mg/m2. An ACM dose of 100 mg/m2/day given for 2 days (total dose, 200 mg/m2) failed to produce significant bone marrow hypocellularity or remission in two patients. Total ACM doses of 300--360 mg/m2 (100 or 120 mg/m2/day x 3 days) produced marrow hypoplasia in 16 to 23 evaluable patients with ANLL. Overall, four of 32 patients with ANLL who received 300--360 mg/m2 of ACM achieved complete remission for duration of 1, 5+, 6 and 15+ months. Two of nine patients with ALL achieved partial remission. Toxic effects of this therapy included severe leukopenia and thrombocytopenia, nausea, mucositis, and diarrhea. ECG abnormalities were noted in 43% of patients who were carefully monitored; however, only one patient developed a significant decrease in left ventricular ejection fraction as measured by radionuclide cardiography. ACM produced only minimal alopecia and did not cause tissue necrosis following inadvertent subcutaneous infiltration. We conclude that 300--360 mg/m2 of ACM is an effective dose for the treatment of patients with ANLL and that further evaluation of this compound is indicated in patients who have received minimal prior therapy.